During the long centuries from the advent of Islam in Iran until the modern times, like the other Islamic territories, in Iran, too, a major portion of issues concerning personal and criminal laws fell under the jurisdiction of the Islamic religious law and, thus, their evolution should be studied under the history of Islamic feqh (jurisprudence). Nevertheless, the important point to bear in mind is that whenever the personal and criminal laws overlapped with the affairs of the government and its authority the case would cease to be merely a religious one and the government would impose its own supervision over it. The most obvious area in which the government imposed its authority was related to trade activities that had been formed and institutionalized under regulations called the “Hesbeh”.Supervision over the affairs of the religious minorities as well as such affairs as the revival of barren lands and the management of heirless property usually fell under the jurisdiction of the government and only during certain periods like the Safavid Era were they treated as religious-government issues. Nevertheless, a long range of personal law issues was always kept out of the jurisdiction of non-religious authorities. Developments such as the actions of Ghazan Khān towards the legislation of laws in the area of strictly prohibiting interest and deceitful transactions as well as the moderation of the mahriyah (dower) rates within the marriage system have been very rare in the history of the Iranian legal system.As regards the issue of criminal laws, political crimes were always kept out of the jurisdiction of religious authorities. Moreover, certain non-political major crimes like murder which could disrupt public law and order fell under the jurisdiction of the governments and, at times, certain laws would be legislated related to crimes that fell out of the purview of religious laws. Very few instances of strict laws dealing with other non-political crimes like the public consumption of alcohol and indecency can be cited in the history of Iranian legal system.